Machine for the production of knitted fabrics



Feb. 9, 1932. I R. K. MILLS 1,844,781

MACHINE FOR THE PRODUCTION OF KNITTED FABRICS Filed Jan. 8, 1930 2 Sheets-Sheet 1 v i F g V e I H L a V 5 V /J/ I V 2 La 1 J7G L.

Feb. 9, 1932. R. K. MiLLs 1,844,781

MACHINE FOR THE PRODUCTION OF KNITTED FABRICS Filed Jan. 8, 1930 2 Sheets-Sheet 2 Eva/ave 7 Patented Feb. 9, 1932 UNITED. STATES PATENT OFFICE ROBERT KIRKLAND MILLS, OI SHERWOOD, ENGLAND MACHINE FOR THE PRODUCTION OF KNITTED IABIB'IGSv Application filed January 8, 1930, Serial No. 419,229, and in Great Britain March 28, 1929. I

production, and said relative movement being such as to cause thread fed to the needle to be looped through and also around or over another loop on said needle.

The passing of a thread loop through and around another loop by means of a plural latch needle as above results in one loop being tied or locked upon another, and the produc tion of a tied or locked loop or number of loops inthis manner in a knitted fabric effectively prevents or minimizes the tendency to unravel or ladder.

In this arrangement the plural latch needle or needles employed in the machine are provided with two latches spaced one below the other. and in such arrangement said needles when operating to produce a tied stitch are first raised to. a position wherein the existing loop thereon is cleared below the bottom latch and new thread is fed between lowered so as to cause the existing loop to be drawn into the needle hook and the newly fed loop to be drawn through said existing loop and pass over or around same.

The plural latch-needle or each of said a needles may, however, be provided with three the two latches, after which the needle isthe nature of this invention reference will now be made to the accompanying drawings, wherein Figure 1 illustrates a suitable arrangement of knitting cams with coacting double latch 66 needles and associated thread feed employed in the present invention for producing a tied stitch. a

Figure 2 illustrates the several successive stepsin the production of a simple formof tied stitch employing a'two latch needle.

Figure 3 illustrates steps in the production of a tied stitch with a three latch needle.

Figure 4 is an enlarged side-elevational view of a two latch needle as employed in this invention.

Figure 5 is a front elevation of the needle shown in Figure 4.

In one method of carrying out the invention a knitting machine is providedwherein a needle a or each of a predetermined number of said needles carries two pivoted latches b, c, on the same side of the shank, said latches being located one above the other and so spaced that the lower latch 0 when raised "15 abuts against the end of the upper latch b when the latter is in the lowered position, said upper latch b when raised being adapted to abut against and close the hook d in the usual manner. y

The manner in which the plural latch needle functions necessarily depends upon the type of stitch or fabric to be produced butthe invention will'first be described as employing a two latch needle as shown in Figure 2. In this arrangement the cam operates upon the needle to elevate same to such a height that the old loop 6 is drawn down over both latches b and c and becomes positioned beneath the lower latch, said latches being in a lowered position as shown atthe third needle from the left in Fig. 2. New thread 7 is then laidon the shank of the needle between the two latches and onthe downward movement of, the needle the lower latch c is raised by the old loop 0 and theend of said latch abuts against or overlaps the extremity of the depending upper latch b, said old loop rising over the two abutting latches and over the newly laid thread loop 7 into the hook d of the needle a, the new loop 7 being thus drawn through the old loop 6 as shown at the fourth needle in Fig. 2. The further downward movement of the needle causes the new loop f to raise the upper latch b and be cast off the needle, thus the old loop is drawn through the new loop and the old loop is re other loop and becomes tied thereon when.

tained in the hook of the needle in readiness for the production of the next stitgh on said needle as shown at the fifth needle in Fig. 2. In this way it will be seen that a loop of thread is passed both through and around a11- the usual tension is applied to the thread. A suitable cam for producing a tied or locked stitch as above is illustrated in Figure 1, the butt of the needle on which a locked stitch is to be formed being caused to travel up the two cam pieces 1, 2, to the position marked 3 at which the old loop 6 is cleared beneath the lower latch, the needle then traveling down beneath cam 4 and taking the newly fed thread 7 from a feeder 6 the beforedescribed intermeshing of the loops 0 and 7 being effected during the downward movement of the needle along said cam 4. e

In order to obviate the possibility of the lower latch 0 being retained in a raised position during the upward movement of the needle for clearing the'old loop 6 and thus preventing the layingof the new thread 7 between the two latches, means are advantageously provided for positively lowering said lower latch 0 during such movement. In one simple method of accomplishing this a small auxiliary cam 5 advantageously provided at a position substantially half-way upthe rise of the needle to the clearing position intermediate the two cam pieces 1 and 2, said auxiliary cam 5 being so designed that when the needle has risen to a position in which the old loop a has passed beneath the extremity of the downturned upper latch 7), see first needle from theleft in Fig. 2, said needle is given a short downward movement to an extent sufiicient to cause the old loop 0 to rise upwardly beueatlrthe upper latch I) and come into position 011 the inner side of the upturned lower latch c, the continued upward movement of the needle along the cam piece 2 then causing the said old loop 6 positively to draw down the lower latch 0 so as to leave the two latches open for permitting the laying of the new thread.

It will be appreciated that in order to accommodate the thread 7 which is fed between the latches b, c, a clearance is required between the needle shank a and the back of the top latch b, and this effect may be accomplished by extending the spoon portion 6 of said latch 5 towards the latch rivet somewhat further than is customary and bending or setting back the tip of-said lengthened spoon b so as to prevent same projecting too far from the shank.

Alternatively, the necessary clearance may be produced by so determining the length of the saw cut in the needle shank as to prevent the latch lying back close on to said shank when opened.

Advantageously the total lateral width at the point where the closed lower latch 0 overlaps the open top latch 6 does not exceed that at the hook d of the needle when the top latch is closed.

Further, the lower latch c is provided with a spoon portion 0 instead of the usual bulb end, and said spoon portion is preferably somewhat wider than that of the top latch and is well cupped so as to fit snugly over the tip of said top latch.

In Figure 3 is shown a needle having three latches, the middle latch g and lowermost latch 7), being each adapted when in their fully raised position to abut against and slightly overlap the latches disposed next above same.

The function of the needle is in this case similar to that before described, the needle being elevated to such position that the old loop 6 passes beyond the lowermost latch h and new thread 7 is laid on the shank of the needle between the middle and lower latches .7:

On the first part of the downward movement of the needle the lowermost latch h is reversed to abut against the middle latch g and the old loop e'guided over the abutting latches and the newlylaid thread f covered thereby, and passing toward the shankof the needle between the upper and middle latches iand 9. On further downward movement of the needle the middle latch g is reversed by the newly laid thread loop f and abuts against the uppermost latch 2'. The newly laid loop is thereby guided over the abutting latches h, 2' covering the old loop 6 and passes toward the hook of the needle; the old thread loop e subsequently Reverses the uppermost latch i and is thereby cast ofl the needle.

Compared with the stitch produced by a two latch needle the result obtained is that the newly formed thread loop f is once more drawn through the old loop e to produce a double intertwining effect.

In the three latch needle suflicient clearance is provided at the rear of the middle latch 7 when open for accommodating the thread f laid between the two latches g, h. I

A cam system for producing this doubly tied stitch would conveniently embody two small auxiliary cams such as-5 (Figure 1) suitably spaced so as to ensure the two latches (7, h being lowered during the rising of the needle to the clearing position.

If desired the book of the plural latch needle may be of spring formation substantially similar to the hook of a bearded needle on the loop being .cast 0E which strain might possibly result in breakage of the loop. If, however, the'hook has a spring action same will yield and allow the loop to pass easily ed the needle.

ll claim: a a

1. In a machine for producing knitted fabrics a needle having a plurality of displaceable latches located one below another on its stem, thread feeding means, means for effecting relative movement between said needle and thread feed for stitch production, and said relative movement being such as to cause thread fed to the needle to be looped through and also around or over another loop on said needle.

2. ln a machine for producing knitted fabrios a knitting needle having two pivoted latches spaced one below another on the needle stem, thread'feedingmeans, cam means functioning to reciprocate said needle, said cam means operating the needle so as first to clear an existing loop thereon beneath the lowermost latch and permit of fresh thread being fed'to said needle between its latches and subsequently to pass aloop of said fresh thread through and also around or over the said existing loop. I

3. In a machine for producing knitted fabrics a needle having three pivoted latches spaced one below the other on the needle shank, athread feed to said needle, means operating on the needle toelevate the same to a position wherein an old loop thereon passes below the lowermost latch and new thread islaid on the needle shank between the middle and lower latches asid needle operating means functioning subsequently to lower the needle so as to cause a loop of the newly laid tHread first to be drawn through the old loop then passed over, or around said loop and subsequently drawn a second time through said old loop so as to produce a double intertwining efi'ect of one loop upon the other.

. operating cam device functioning 4. In ama-chine for producing knitted fabies, a needle having a'plurality of pivoted latches spacedone below the other on the needle stem, the extremity of said latches being adapted to abut or overlap when extending in opposite directions, thread feeding means to said needle, a cam device functioning to displace the needle to a position wherein thread is fed between the latches,

thereon and subsequently to cause a loop of newly fed thread to pass through and also around an existing loop. on said needle, and an auxillary cam associated with said needle to move the latches apart for permitting the feedmg of new thread between same.

ROBERT KIRKLAND MILLS.

positively 

